Scalable hosting packages - WHMCS/Cloudlinux

I need help on custom development for WHMCS plateform. On the plateform, I use 3 types of products : 1) hosting packages : quite simple, packages are already set on WHM server. No problem! 2) cloud server : we open the server manually and manage it throw DigitalOcean and Runcloud. This process is alright for now. 3) scalable hosting performances : here is the real trick. We create packages on our dedicated server. Customers have the ability to set their : - CPU - RAM - disk space - domain number associated Those settings are set in WHM directly and Cloudlinux too! If french doesn't scare you, you can find how this is displayed here : [login to view URL] You can see that many settings can be offered to the customer. That means a LOT of packages to create if we want every combination. For now, here is how those services are offered : [login to view URL] Quite ugly, right? So I need help on that matter for several things : A- I would like customers to be able to choose their CPU/RAM/space/domains themselves, on some kind of slider like this : [login to view URL] This can be done on WHMCS or WordPress (connected to WHMCS) itself. B- As you can guess, we didn't create every possible package there is, there are too many of them. We would like to have advices on that matter. Maybe to have the ability to create the package directly on WHM/Cloudlinux if the package doesn't exist? ... if that's possible. Or maybe help us import every possible listing combination on WHMCS/WHM? C- We shouldn't forget about existing customers that wants to downgrade or upgrade their hosting services. That should be possible too. I need somebody that is sure to help us on this challenge. Need estimate and please explain how you may proceed (no need for details tho). Thanks a lot.